We excluded cases in which injury was related to swallowing items other than swords, such as . . . jack hammers.

As well they should!

Brian Witcombe, a physician, and Dan Meyer, an executive in a professional organization for sword swallowers, published an article in a 2006 issue of the British Medical Journal. It evaluated the health risks of sheathing a sword inside the human esophagus. They surveyed 46 sword swallowers and determined that performers increase the likelihood of injury by “adding embellishments to their performance.”

Who engages in this performing art? Amy Kraft of The Week attended a meeting of sword swallowers. It was one of many held simultaneously at Ripley’s Believe It or Not locations around the United States. She writes that sword swallowing originated in India about 4,000 years ago. It requires careful and rigorous training:

To get there, you must first learn to suppress the gag reflex in the back of your throat, which sword swallowers work on for years. Then you have to flip back your epiglottis and relax several other involuntary muscles in the esophagus, which winds past major organs, including the heart. Finally, to get the sword into the stomach you have to relax the lower sphincter muscle and repress the stomach's retch reflex.